Virtualization techniques in which a plurality of operating systems (OSs) are concurrently run on a single computer have been widely used from servers to embedded devices. The use of the virtualization techniques makes it possible to monitor access to peripherals.
ARM TrustZone (registered trademark) has a memory protection function. In an ARM processor, buffers and registers of the peripherals are mapped in a memory space. The access to the peripherals thus can be monitored. The ARM TrustZone, however, has no clear functional structure to securely filter the access to the peripherals. The virtualization of peripherals needs a structure to perform conversion of contents of the access to the peripherals by filtering the access such as encryption.